#include "usbtransfers.h"

#define HANDLE_CTX(handle) (DEVICE_CTX((handle)->dev))
#define DEVICE_CTX(dev) ((dev)->ctx)

struct list_head {
	struct list_head *prev, *next;
};

struct libusb_device {
	/* lock protects refcnt, everything else is finalized at initialization
	 * time */
	pthread_mutex_t lock;
	int refcnt;

	struct libusb_context *ctx;

	uint8_t bus_number;
	uint8_t device_address;
	uint8_t num_configurations;
	enum libusb_speed speed;

	struct list_head list;
	unsigned long session_data;
	unsigned char os_priv[0];
};

struct libusb_device_handle {
	/* lock protects claimed_interfaces */
	pthread_mutex_t lock;
	unsigned long claimed_interfaces;

	struct list_head list;
	struct libusb_device *dev;
	unsigned char os_priv[0];
};

static void LIBUSB_CALL i3_bulk_transfer_cb( struct libusb_transfer *transfer )
{
    int *completed = (int*)( transfer->user_data );
	*completed = 1;
	// printf( "actual_length = %d\n", transfer->actual_length );
	/* caller interprets results and frees transfer */
}

int do_i3_bulk_transfer( struct libusb_device_handle *dev_handle,
                                unsigned char endpoint, unsigned char *buffer, int length,
                                int *transferred, unsigned int timeout, unsigned char endpoint2,
                                unsigned char *buffer2, int length2, int *transferred2,
                                unsigned int timeout2 )
{
    //struct libusb_transfer *transfer = libusb_alloc_transfer( 0 );
    struct libusb_transfer *transfer = libusb_alloc_transfer( 1 );
	int r;
    int completed = 0;

	if( !transfer )
    {
		return LIBUSB_ERROR_NO_MEM;
    }

	libusb_fill_bulk_transfer( transfer, dev_handle, endpoint, buffer, length, i3_bulk_transfer_cb, &completed, timeout );
	transfer->type = LIBUSB_TRANSFER_TYPE_BULK;

    // send reqquest to #3
	r = libusb_submit_transfer( transfer );
	if (r < 0) {
		libusb_free_transfer( transfer );
		return r;
	}

    // send request to #2
    libusb_bulk_transfer( dev_handle, endpoint2, buffer2, length2, transferred2, timeout2 );

	while( !completed )
    {
		r = libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed );
		if( r < 0 )
        {
			if( r == LIBUSB_ERROR_INTERRUPTED )
            {
				continue;
            }
			libusb_cancel_transfer( transfer );
			while( !completed )
            {
				if( libusb_handle_events_completed( HANDLE_CTX( dev_handle ), &completed ) < 0 )
                {
					break;
                }
            }
			libusb_free_transfer( transfer );
			return r;
		}
	}

	*transferred = transfer->actual_length;
	switch (transfer->status) {
	case LIBUSB_TRANSFER_COMPLETED:
		r = 0;
		break;
	case LIBUSB_TRANSFER_TIMED_OUT:
		r = LIBUSB_ERROR_TIMEOUT;
		break;
	case LIBUSB_TRANSFER_STALL:
		r = LIBUSB_ERROR_PIPE;
		break;
	case LIBUSB_TRANSFER_OVERFLOW:
		r = LIBUSB_ERROR_OVERFLOW;
		break;
	case LIBUSB_TRANSFER_NO_DEVICE:
		r = LIBUSB_ERROR_NO_DEVICE;
		break;
	default:
		WRN << "unrecognised status code" << transfer->status;
		r = LIBUSB_ERROR_OTHER;
	}

	libusb_free_transfer( transfer );
	return r;
}


int do_i3_bulk_transfer_multi( struct libusb_device_handle *dev_handle,
                                unsigned char endpoint, unsigned char *buffer, int length,
                                int *transferred, unsigned int timeout, unsigned char endpoint2,
                                unsigned char *buffer2, int length2, int *transferred2,
                                unsigned int timeout2 )
{
    //struct libusb_transfer *transfer = libusb_alloc_transfer( 0 );
    struct libusb_transfer *transfer = libusb_alloc_transfer( 1 );
	int r;
    int completed = 0;

	if( !transfer )
    {
		return LIBUSB_ERROR_NO_MEM;
    }

	libusb_fill_bulk_transfer( transfer, dev_handle, endpoint, buffer, length, i3_bulk_transfer_cb, &completed, timeout );
	transfer->type = LIBUSB_TRANSFER_TYPE_BULK;

    // send reqquest to #3
	r = libusb_submit_transfer( transfer );
	if (r < 0) {
		libusb_free_transfer( transfer );
		return r;
	}

    // send request to #2 twice
    libusb_bulk_transfer( dev_handle, endpoint2, buffer2, length2, transferred2, timeout2 );
    libusb_bulk_transfer( dev_handle, endpoint2, buffer2, length2, transferred2, timeout2 );

    while( !completed )
    {
		r = libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed );
		if( r < 0 )
        {
			if( r == LIBUSB_ERROR_INTERRUPTED )
            {
				continue;
            }
			libusb_cancel_transfer( transfer );
			while( !completed )
            {
				if( libusb_handle_events_completed( HANDLE_CTX( dev_handle ), &completed ) < 0 )
                {
					break;
                }
            }
			libusb_free_transfer( transfer );
			return r;
		}
	}

	*transferred = transfer->actual_length;
	switch (transfer->status) {
	case LIBUSB_TRANSFER_COMPLETED:
		r = 0;
		break;
	case LIBUSB_TRANSFER_TIMED_OUT:
		r = LIBUSB_ERROR_TIMEOUT;
		break;
	case LIBUSB_TRANSFER_STALL:
		r = LIBUSB_ERROR_PIPE;
		break;
	case LIBUSB_TRANSFER_OVERFLOW:
		r = LIBUSB_ERROR_OVERFLOW;
		break;
	case LIBUSB_TRANSFER_NO_DEVICE:
		r = LIBUSB_ERROR_NO_DEVICE;
		break;
	default:
        WRN << "unrecognised status code" << transfer->status;
		r = LIBUSB_ERROR_OTHER;
	}

	libusb_free_transfer( transfer );
	return r;
}

static unsigned short fcstab[256] = {
    0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
    0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
    0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
    0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
    0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
    0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
    0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
    0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
    0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
    0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
    0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
    0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
    0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
    0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
    0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
    0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
    0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
    0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
    0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
    0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
    0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
    0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
    0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
    0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
    0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
    0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
    0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
    0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
    0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
    0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
    0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
    0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};

u16 pppfcs16( register unsigned short fcs, const unsigned char *cp, register int len )
{
    while( len -- )
    {
        fcs = ( fcs >> 8 ) ^ fcstab[ ( fcs ^ *cp++ ) & 0xff ];
    }
    return fcs;
}

void DoFcs16( unsigned char *cp, int len )
{
    u16 trialfcs;

    trialfcs = pppfcs16( PPPINITFCS16, cp, len );
    trialfcs ^= 0xffff;
    cp[ len ] = ( trialfcs & 0x00ff);
    cp[ len + 1 ] = ((trialfcs >> 8) & 0x00ff);
}

u32 EscapeInRequest( InRequest *ir, u8* outBuf )
{
    u32 irPos = 1;
    u32 outPos = 1;

    const u8* irB = (const u8*)ir;
    for( ; irPos < sizeof( InRequest ) - 1; irPos++ )
    {
        if( irB[ irPos ] == 0x7e || irB[ irPos ] == 0x7d )
        {
            outBuf[ outPos++ ] = 0x7d;
            outBuf[ outPos++ ] = irB[ irPos ] - 0x20;
            continue;
        }
        outBuf[ outPos++ ] = irB[ irPos ];
    }

    // first and last bytes are always 0x7e
    outBuf[ 0 ] = 0x7e;
    outBuf[ outPos++ ] = 0x7e;

    // return the new length
    return outPos;
}

bool CheckFcs( const u8* d, u32 len )
{
    u16 fcs = pppfcs16( PPPINITFCS16, d, len );
    fcs ^= 0xffff;

    u16 fcsA = ( d[ len + 1 ] << 8 ) | d[ len ];
    bool ret = fcsA == fcs;
    if( !ret )
    {
        WRN << "Fcs doessn\'t match" << fcs << fcsA;
    }
    return ret;
}

void UnEscapeMessage( u8* d, int &len )
{
    u32 off1 = 0;
    u32 off2 = 0;
    u32 l = len;

    for( ; off1 < l; off1++, off2++ )
    {
        if( d[ off1 ] == 0x7d )
        {
            d[ off2 ] = d[ ++off1 ] + 0x20;
            len --;
        }
        else
        {
            d[ off2 ] = d[ off1 ];
        }
    }
    //DBG << len;
    //hexdump( d, len );
}

void UnEscapeMessage( u8* s, u8* d, int &len )
{
    u32 off1 = 0;
    u32 off2 = 0;
    u32 l = len;

    for( ; off1 < l; off1++, off2++ )
    {
        if( s[ off1 ] == 0x7d )
        {
            d[ off2 ] = s[ ++off1 ] + 0x20;
            len --;
        }
        else
        {
            d[ off2 ] = s[ off1 ];
        }
    }
    //DBG << len;
    //hexdump( d, len );
}

void EscapeMessage( const u8* inB, u8* outBuf, u32 &len )
{
    u32 inPos = 0;
    u32 outPos = 0;

    for( ; inPos < len; inPos++ )
    {
        if( inB[ inPos ] == 0x7e || inB[ inPos ] == 0x7d )
        {
            outBuf[ outPos++ ] = 0x7d;
            outBuf[ outPos++ ] = inB[ inPos ] - 0x20;
            continue;
        }
        outBuf[ outPos++ ] = inB[ inPos ];
    }

    // return the new length
    len = outPos;
}
